Metal cutting tools

Abstract

Metal cutting tools, such as drills or reamers, utilized to produce holes with substantially improved finishes and sizes at faster speed and feed rates having a double cutting action, said tool comprising a reamer having a plurality of cutting flutes with a 45° primary cutting surface and a tapered secondary cutting surface, the primary surface including slots or grooves thereon, and each flute may have a margin on the O.D. of the flute or a relief angle to provide accurate cutting operations.

1 . A metal cutting reamer comprising: a plurality of flutes with primary cutting edges ground at a 45° angle, and secondary longitudinally extending tapered shaving edges provided with margins.  
     
     
         2 . A metal cutting reamer as set forth in  claim 1 , wherein said margins are in the range of 0.002 to 0.020 inch wide.  
     
     
         3 . A metal cutting reamer as set forth in  claim 1 , wherein said margins are in the range of 0.004 to 0.015 inch wide.  
     
     
         4 . A metal cutting reamer as set forth in  claim 1 , wherein said tapered edges are less than 0.20 inch long.  
     
     
         5 . A metal cutting reamer as set forth in  claim 1 , wherein said tapered edges are less than 0.15 inch long.  
     
     
         6 . A metal cutting reamer as set forth in  claim 1 , wherein said tapered edges are less than 0.10 inch long.  
     
     
         7 . A metal cutting reamer as set forth in  claim 2 , wherein said tapered edges are less than 0.20 inch wide.  
     
     
         8 . A metal cutting reamer as set forth in  claim 1 , wherein said shaving edges are provided with slots or grooves less than 0.002 inch deep and spaced apart less than 0.020 inch and greater than 0.0001 inch wide.  
     
     
         9 . A metal cutting reamer as set forth in  claim 8 , wherein said slots or grooves are positioned to provide, adjacent to the primary cutting edges, a short length of straight shave edges of not less than 0.010 inches.  
     
     
         10 . A metal cutting reamer as set forth in  claim 1 , wherein said tapered edges are angled less than 4° with respect to the centerline of the reamer.  
     
     
         11 . A metal cutting reamer as set forth in  claim 1 , wherein said tapered edges are angles less than 2° with respect to the centerline.  
     
     
         12 . A metal cutting reamer as set forth in  claim 1 , wherein said tapered edges are angled less than 1° with respect to the centerline.  
     
     
         13 . A metal cutting reamer as set forth in  claim 2 , wherein said tapered edges are less than 0.20 inch long and are angled less than 4° with respect to the centerline.  
     
     
         14 . A metal cutting reamer as set forth in  claim 8 , wherein said tapered edges are angled less than 4° with respect to the centerline.  
     
     
         15 . A metal cutting reamer as set forth in  claim 9 , wherein said tapered edges are angled less than 4° with respect to the centerline.  
     
     
         16 . A metal cutting reamer comprising: a plurality of flutes on the cutting end with primary cutting edges ground to a 45° angle and secondary longitudinally extending shaving edges, each edge being provided with a relief angle providing a sharp edge.  
     
     
         17 . A metal cutting reamer as set forth in  claim 16 , wherein said tapered edges are less than 0.20 inch long.  
     
     
         18 . A metal cutting reamer as set forth in  claim 16 , wherein said shaving edges are provided with slots or grooves less than 0.002 inch deep and spaced apart less than 0.020 inch and greater than 0.0001 inch wide.